Co-treatment with caffeine significantly decreased these upregulations at all time points investigated, while caffeine without phenobarbital resulted in increased expression of TNFα, IL-1β, and IL-18, but not IFNγ at 6 h. Downregulation of the adenosine A1 and A2a receptors, both of which bind caffeine, by 24 h of phenobarbital exposure was partly antagonized by caffeine.
The human airway epithelial cell line H441 and the fetal lung fibroblast strain IMR-90 were exposed to different glucocorticoids (dexamethasone, budesonide, betamethasone, prednisolone, hydrocortisone) and caffeine. mRNA and protein expression of CTGF, TGF-β1-3, and TNF-α were determined by means of quantitative real-time PCR and immunoblotting.
These data suggested that javamide-II may be a potent compound to suppress TNF-α production more efficiently than caffeine by inhibiting ERK phosphorylation in Jurkat cells.